Infestation of Early- and Late-Flushing Trees by Spring Caterpillars: An Associational Effect of Neighbouring Trees

In temperate forests within Europe, early-flushing (EF) deciduous trees are often heavily infested by early spring leaf-eating Lepidoptera, while late-flushing (LF) better protected in a phenological manner against such heavy infestations, as moth larvae begin to appear before their bud burst. The associational effects of EF on LF ones only poorly known. We studied whether or not the infestation Lepidoptera can be affected if they grow immediate vicinity. compared assemblages Quercus cerris L. with those Q. pubescens Willd. several microhabitats Slovakia, Central Europe. Larvae were collected from mature and young trees. Mature sampled growing: (1) closed-canopy forest; (2) small groups; (3) lone tree. Forest tree groups both constituted oak species. Tree 20–50 m distant forest edges. Young growing under gaps near where (Q. cerris) surrounded pubescens), caterpillars abundance, almost ones. species composition larval two was similar. contrast, trees, lepidopteran significantly less abundant than case abundance oaks comparable forest. open habitat, differed between two. Our results reveal effect (associational susceptibility) when close It means that protection may sufficient